COST: Admission for two visits during 10 consecutive days is $25 for adults and free for ages 17 and under on weekends and weekdays after 3 p.m. Otherwise $10. The Magna Carta Boston History pass is $42 for adults and $12 for ages 3 to 12)

It may seem unpatriotic to praise the British on July 4. But the Founding Fathers relied on a British document to justify their right to rebel.

That document – the nearly 800-year-old Magna Carta – is making a rare appearance at the Museum of Fine Arts, in the exhibit “Magna Carta: Cornerstone of Liberty,” which opened yesterday and runs through Sept. 1. One of only four surviving copies, it paradoxically looks as durable and fragile as the freedoms it protects.

“I hope you will stand before it in awe and wonder at its age, its history, its influence,” said The Very Reverend Philip Buckler, dean of Lincoln, the cathedral that owns the 1215 copy on display. “I hope you will look after it.”

Set on a tilted lectern inside a clear plexiglass enclosure, the Magna Carta is 4,000 Latin words written in brown ink, now faded and blurred, on a 20-by-17-inch patch of creased cream-colored sheepskin. For about 600 years, it lay folded in a drawer in the cathedral before being discovered, said the Rev. Buckler, who attended a private unveiling for invited guests Monday in the Art of the Americas wing of the MFA. Most of the roughly 20 to 30 copies given to Britain’s main centers of power in 1215 were destroyed when the Pope annulled the Magna Carta, the Rev. Buckler said.

The Magna Carta – which means Great Charter – laid the foundation for modern concepts of justice, due process, trial by jury and civil rights. It was written by the English barons to limit the king’s power and was reluctantly signed by King John following the British Civil War. It had a profound influence on the American revolutionaries who wrote the Declaration of Independence, the Bill of Rights and the U.S. Constitution.

“We think of the revolutionaries as making something new, but the reality is that they thought they were restoring their liberties,” said Peter Drummey, librarian of the Massachusetts Historical Society. “They wanted their rights returned to them.”

For the public, the Magna Carta’s impact is more understandable because of the roughly 20 exhibit pieces – with explanatory text – that surround it. These come from the collections of the MFA and the Massachusetts Historical Society.

“I love the way the MFA has displayed it,” said Cory Atkins, a Democratic state representative from Concord who grew up in Marshfield and was influential in bringing the Magna Carta to the United States. (The state Legislature provided a $100,000 loan). “You get a sense of its age and fragility and its influence.”

Along with busts of Founding Fathers John Adams and Thomas Jefferson, there’s a John Singleton Copley portrait of Samuel Adams. In the painting, Adams points to the Charter of Massachusetts Bay, which affirmed many of the liberties in the Magna Carta. Adams wrote in 1765 that the charter “is ... as sacred (to Bostonians)... as Magna Carta is to the People of Britain.”

Page 2 of 2 - Also on exhibit are manuscripts of drafts of the Declaration of Independence, penned by John Adams and Thomas Jefferson, a draft of the Massachusetts constitution, and an annotated copy of the Constitution, all loaned by the Massachusetts Historical Society.

A highlight of the exhibit is the Sons of Liberty Bowl, a silver bowl made and engraved by Paul Revere in 1768 with the words “Magna Carta.” Paul Revere also summoned the Magna Carta in several etchings that are on display.

Two hundreds years after the Revolution, the Magna Carta remained part of political reference. In 1958, U.S. Sen. John F. Kennedy delivered his “Time for an Urban Magna Carta” speech at a mayor’s conference, calling upon cities to address the inequality that restricts freedom. A black-and-white photograph of Kennedy shows him in profile, hands clasped, as though praying for the realization of America’s ideals.

To enhance the exhibition, the MFA is offering a Magna Carta Boston History Pass, which combines museum admission with a Freedom Trail walking tour and admission to the Old State House, the Old South Meeting House and the Paul Revere House.

When the Magna Carta leaves the MFA, it will go to The Sterling and Francine Clark Art Institute in Williamstown and then the Library of Congress in Washington, D.C. In 2015, England will celebrate its 800th anniversary with an exhibition that brings together all four original surviving manuscripts.

Jody Feinberg may be reached at jfeinberg@ledger.com. Follow her on Twitter @JodyF_Ledger.